GSTZ1 (Glutathione S-Transferase Zeta 1) is a Protein Coding gene. 3 alternatively spliced human isoforms have been reported. GSTZ1 gene is a member of the glutathione S-transferase (GSTs) super-family which encodes multifunctional enzymes important in the detoxification of electrophilic molecules, including carcinogens, mutagens, and several therapeutic drugs, by conjugation with glutathione. GSTZ1 is a bifunctional protein that has minimal glutathione-conjugating activity with ethacrynic acid and 7-chloro-4-nitrobenzo-2-oxa-1,3-diazole and maleylacetoacetate isomerase activity. GSTZ1 catalyzes the glutathione-dependent oxygenation of dichloroacetic acid to glyoxylic acid. GSTZ1 participates in the catabolism of phenylalanine and tyrosine. Thus defects in GSTZ1 cause harsh metabolic disorders including alkaptonuria, phenylketonuria, and tyrosinemia.